What causes a SPN 726 code?

SPN 726 can be triggered by several issues — see the verified probable causes and step-by-step diagnostics shared by mechanics and owners on OBDIY.

Can I drive with a SPN 726 code?

Drivability depends on the severity. Check the severity rating and verified driver reports on this page before continuing to drive with SPN 726 active.

How do I fix SPN 726?

Follow the step-by-step diagnostic on this page, then read the verified fixes contributed by other Heavy Truck owners — the answer marked "Verified Cause" worked for the original poster.

OBDIY

J1939 SPN

SPN 726

J1939 SPN 726 — Engine Management parameter

What it means

SPN 726 indicates a communication or data mismatch regarding the J1939 network's 'Auxiliary Vacuum Pressure' or, more commonly in modern truck configurations, a general Engine Management Parameter timeout related to the body-to-engine interface.